MemOS

AFFiNE brings documents, an edgeless whiteboard, databases, knowledge management, and planning into one workspace. Rich text, notes, web embeds, linked pages, shapes, and slides can coexist on the same canvas, while local-first storage is paired with cross-platform synchronization and real-time collaboration. The Community Edition can be self-hosted, and optional AI features can turn material into reports, slides, mind maps, or plans. It suits people who want fewer boundaries between note-taking and visual thinking.

PrivateGPT sits between an OpenAI-compatible local inference server and the applications built on top of it. Its API covers messages, file ingestion, citation-backed retrieval, custom tools, database and CSV access, and MCP connectors, following the Claude API as a reference. The included web interface is mainly a demonstrator and debugger; developers are expected to build their own user experience around the API.

Appwrite brings common application backends into one platform so web, mobile, and AI teams can avoid assembling a fragmented stack. It covers identity and data management, file storage, server-side functions, realtime communication, and web hosting. Teams can use the managed cloud or self-host in Docker, Kubernetes, and other container environments, then connect through SDKs or REST, WebSocket, and GraphQL APIs.

SiYuan organizes personal knowledge around content blocks, bidirectional links, and a WYSIWYG Markdown editor, allowing references, queries, PDF annotations, and tasks to live in one workspace. It offers desktop and mobile apps, can be self-hosted with Docker, and exports to formats including Markdown, PDF, Word, and HTML for users who want stronger control over their data.